Top lift attachment for lift truck



April 6, 1965 H. s. MEISTER, JR

TOP LIFT ATTACHMENT FOR LIFT TRUCK Filed July so. 1962 2 Sheets-Sheet l HARRY G. MEISTER, JR.

5) BUCKHORN, CHEATHAM 8 BLORE A T TORNE YS H. G. MEISTER, JR

TOP LIFT ATTACHMENT FOR LIFT TRUCK April 6, 1965 2 Sheets-Sheet 2 Filed July 50, 1962 IN VE/V TOR HARRY G. ME ISTER, JR

5') BUCKHORN, CHEATHAM a BLORE ATTORNEYS United States Patent Ofific Patented Apr. 6, rose 3,176,866 TOP LIFT ATTACHMENT FOR LET TRUCK Harry G. Meister,,.lr., Portland,,0reg., assignor to Hyster Company, Portlanmflreg, a corporation of Nevada Filed July 30, 1962, Ser. No. 213,368 2 Claims. (Ql. filo-62$) This invention relates to an attachment for a fork lift truck, and particularly to an attachment which enables the truck to lift, by the top, a box or container having top lifting lugs.

Certain kinds of boxes or containers are constructed with passages or spaces therebeneath to receive the forks of a lift truck so that a box may be more readily handled by such a truck. During the many handling and transporting operations of such a box, there are times when the lower portions of a box are not accessible to the forks of a lift truck, such as for instance when the box occupies a position in a railway gondola car. To enable the box to be lifted under these circumstances, the box is provided with lugs at its top, which are accessible and which facilitate lifting of the box by a crane with the aid of cables connected to the lugs. However, after a box is removed from the gondola by the crane, the box can be transported and handled more easily and rapidly by a fork lift truck; Thus, it is common practice to utilize a crane to lift the boxes out of a gondola, and then to utilize a fork lift truck to handle the boxes thereafter.

It is a main object of the present invention to provide an attachment for a fork lift truck which will enable the above described top lifting operations tobe readily: carried out, thereby eliminating the necessity for a crane It is a more specific object of the present invention to provide an attachment for a fork lift truck which can be readily mounted on the forks of the lift truck by the operator without the aid of other equipment, and which will enable boxes of the type. under discussion to be lifted from the top and unloaded from places of the type described above, and which attachment can then be readily detached from the forks to enablethe boxes to be lifted from the bottom.

Various other objects of the invention will be apparent from the following description taken. in connection with the accompanying drawings wherein:

FIG. 1 is a side elevational view of a fork lift truck having an attachment of the invention shown as lifting a box from the top;

FIG. 1A is a fragmentary perspective view of a box of the type to be picked up;

IGS. 1B and 1C are views like FIG. 1 but on a small scale, and show handling a half-width container;

FIG. 2 is a perspectiveview of the attachment on a scale larger than that employed in FIG. 1;

FIG. 3 is a rear. elevation of the attachment taken in the direction of the arrows 3-3 of FIG. 1, showing in broken lines portions of the box and fork arms;

FIG. 4 is a fragmentary vertical sectional view taken along line 44 of FIG. 3, showing in broken lines portions of the box and fork arms;

FIG. 5 is aside elevational View of the attachment, on a reduced scale from that employed-in FIGS. 3 and 4,,show ing in broken lines its relationship to the fork arms and the box; p

FIG. 6 is a vertical sectional view taken along line 6-6 of FIG. 5; and p FIG. 7.is a fragmentary. plan view takenint-he direction of the arrows 7-7 of FIG. 4.

Referring to. FIG. 1 the lift truck T has the usual mast 13' which is tiltable back and forth "under the influence of a tilt mechanismlS. Movable along the mast under the influence ofthe usualram (not shown) is a load carriage C having a pair of fork arms F. The arms support an attachment A of the present invention, which attachment gas hooks 21 engaging lugs 23 provided on the top of a ox B.

The attachment is best shown in FIG. 2 and comprises an open frame or body including two spaced parallel side members 31 connected by two spaced parallel cross mern bers 33 and 35. Cross member 33 is disposed at the righthand or rear ends of the side members, whereas cross member 35 is consideralby spaced from the left-hand or front ends of the side members.

The side and top members are shown in the form of I beams (or wide flanges in the case of the cross members), with the cross members being of lesser thickness than the side members and positioned with their upper surfaces near the upper surfaces vof the side members to substantially space the lower surfaces of the cross members above the lower surfaces of the side members.

Secured to the underside of the front cross member 35 are a pair of U-shaped guides 37 (FIGS. 1 and 6) providing slots to receive the horizontal portions of the fork arms F. The guides are located just inwardly of the side members 31 and have a depth substantially greater than the thickness of the fork arm, and a width somewhat greator than the width of a fork arm for purposes to appear presently.

A similar pair of U-shaped guides 3h (FIGS. 1 and 3) are secured to the underside of a rear cross member 33.

Each of the guides provides slots to receive the horizontal portions of the fork arms F and also movably receives the forward portion of a retainer unit R (FIGS. 1, 4 and 7) of open rectangular form. Each retainer unit has a pair of side pieces 43 (FIG. 7) which are spaced. apart a dis-' tance greater than the width of afork arm F, and a pair of cross pieces 45 and 47 whichare secured'to the top edges of the side pieces. The cross piece 45 (FIGS. 4 and 7) has an upstanding clevis 49 which straddles a fixed locating arm 51 on the cross member 33; A pivot pin 52 fits through thecle'vis 49 and through one of several longitudinally spaced holes 53 (FIG. 4) provided in the arm 51.

The retainer units R are dimensioned so that. the forkarm F received by the retainer units engage the lowersurfaces of the cross, member 33 in generally parallel load transmittingrelation thereto as is apparent from FIG. 4.

Preferably each of the pivot pins 52 is of the quick detach type and is tied by a short wire or cable (notshown) to the retainer, and has a hole to receive a lock pin 57 (FIG. 7) which preferably is also tied'to the retainer to prevent loss of the parts when separated from.

At the rear ends of the side pieces 43 of each retainer R is a retaining pin 61 which is preferably of the quick de tach type. This pin is located below the level of the cross piece 47 by a distance less than the thickness of'the horizontal portion ofthe fork arm F, and is spaced rearwardly from the cross piece by a distance slightly greater than the thickness of the vertical portion of the associated fork arm so as to accommodate the fork arm and releasably connect the fork arm to the retainer R and thus releasably connect the attachment A to thefork arm F. Thus the pins 61, cross pieces 47 and side pieces 43 constitute latches releasably connecting the attachment A to the fork arm F.

Slidably mounted on the side members 31 of the frame of the attachment A are a pair of rear box engaging devices D and a pair of front box engaging devices D To more readily understand the construction of the devices of a -U-shaped pieceof metal.

slightly below its fully operative position.

D and D and their purposes, a brief description of V the type' of box B to be picked up will be given. 7 a Referring particularly to FIG. 1A, the box B is recessed r grooved along two of. the upper edges thereof to provide at each edge a horizontal shoulder 71 and a vertical face 73 which together define a recess or groove. An upstanding ear 75 is provided at each'end portion of each horizontal shoulder and each ear is located so that In fact, the

it is spaced from the associated face 73. ears are shown located so thatthe outer face of an ear is substantially flush with the adjacent'side' of the box. The lifting lugs 23 (previously mentioned) are in the form of horizontal rods which connect the cars '75 to the vertical'faces '73 in spaced relation above the horizontal shoulder 71 to enable the hooks 21 to fit there- 7 symmetrical relation to the side edges of the base plate is an elongated gauge pad 83 which is shown in the form The pad is located in spaced relation from the rear end of'the base plate but adjacent the front end thereof. At the front end of the base plate, there are a pair of upstanding guide lugs 85 disposed in sliding contact with the side edges of the lower flange 82 of the associated side member 31.

Referring particularly to FIG. 3,- disposed at the rear portion of the base plate 81 in spacedrelation from' the gauge pad 83 are a pair of hanger brackets 67 of roughly sickle shape, which embrace the lower flange 82 of the member 31 and also the base plate, and are bolted to the base plate. 'The hanger brackets 87 have 'upper portions disposed on opposite sides of the web 88 of the associated member 31 in clevis-like fashion. A quick detach pin 89 fits through'holes in such upper portions and through a hole in such web to releasabl retain the device D in a desired position.

Secured centrally to the underside of the base plate at its rear portion is the hook 21 for the box engaging device, the hook facing forwardly toward the associated pad 83.

The front box engaging devices D are similar to the rear devices D but have several differences. The base plates 81a thereof are shorter than the base plates 81 of the rear'devices. In fact,:they are sufficiently shorter that the hooks 21 thereof abut against the pads 83 thereof, as is apparent from'FIG. 5. Also, the hooks 21 and the hanger brackets 87 are disposed forwardly of the pads S3 rather than behind the pads. Such hooks,

however, face in the same direction as do the hooks 21 of the rear devices D ,'i.e., forwardly.

It is apparent, from FIGS. 3 and 6, the distance between the inner faces of the gauge pads 83 of the devices D and D is somewhat greater than the distance between,

the vertical faces 73 of the recesses of the box B to enable the pads to readily fit into the recesses of the box B. It is obvious that the spacing between the pads 83 is .such that they will conceivably engage the shoulders 71,

that is to say, the pads are spaced a distance aPProXimately the same as thatv of the shoulders 71. 1

that the lower surface thereof-is spaced slightly above the associated shoulder 71 when the associated hook 2 is in fully operative engagement with the associated lug 23. This means that when the pad 83 rests against the shoulder 71, the associated hook 21 will be disposed This enables the raised end portion 21a (FIG. 4) of the hook 21 to readily pass beneath the lug 23 when the attachment A is being maneuvered into engagement with the box l3. FIG. 4 also shows that when the hook 21 is in fully V operative engagement with the lug 23, the pad 83 0f the device D is spaced forwardly of the associated ear '75 of the box B. This spacing is such that the hook 21 can occupy an inoperative position substantially behind thelug23 while the pad 83 is in engagement with the shoulder 73 at a place forwardly of the ear 75'. This relationship of parts is not necessary for the front devices D because the hooks 21 of such devices are in front of the associated pads 83, rather than behind such pads.

Endv plates 92. are provided for the members '31 and strengthen the members... They also function as stops to limit travel of the devices D and D Operation 39) and then throughthe front guides 37, until the vertical portions of the fork arms F abut against the cross pieces 47. Then the retainer pins 61 are reinserted into place so that the attachment A is now connected to the fork arms F. 7 It is apparent that this operation of mounting the attachment A'on the fork arms Fcan be carried out by the operator of'the truck without assistancefrom others and without requiring the use, of tools.

The lift ram of the truck is now operated to'lift the carriage C, the fork arms F and attachment A, and the truck is' driven to a gondola and, maneuvered to locate the attachment A in' a, position overlying a box B with the pads 83 approximately aligned with the recessesof the box, and to locate the pads 83 andthe associated hooks 21 in straddling relation to the rear ears 75 of the 'box. Now, the attachment A is lowered to bring the pads 83 into engagement with the shoulders {71 of the recesses. This serves to locate the hooks 21 behind the lifting lugs 23 and at the proper .level for engagement with such lugs upon forward movement of the attachment. Y The truck is now driven forwardly a short distance to bring the hooks into engagement with lifting lugs. Thereafter, the attachment is elevated slightly to bring the hooks into fully operative engagement with the lugs.

Continued elevation of the attachment will lift the box B out of the gondola car. The truck may now be backed up and then driven to a desired depositing station. Instead, the box B may be unloaded on the ground or other supporting surface near the gondola car to permit another fork lift truck to lift the box by engagement of fork arms' under the box in suitable passages provided by runners 91 (FIG. 1) or a number of boxes may be removed from one or more gondola cars and deposited on Thereafter, the attachment A' the boxes 3 from the gondola cars can be used to lift the boxes B from the bottoms thereof and transport them elsewhere for individual deposit, stacking or the like.

It has been assumed in describing the above operations that the operator of the truck initially maneuvered the truck so that the attachment A was disposed in superposed relation to the box B with the pads 83 substanthe pads, and shoulders will not be attained, and this will occur? more often with unskilled operators than with skilled'ones.

Theattachment A is so constructed that proper alignment canbe "obtained; despite" initial misalignment; with out'requiringthe o eratefito try"'ag'ain"and"again for proper alignment by driving the truck back and forth.

Rt'e'rring'to' FIG. 3,'it was previously mentioned that the pads. 83 are of- U-shapc, and thus the flower inner corneis" 83a thereof are" 'curved or rounded. It follows that when lowering the attachment onto the box from a misaligned position above the'bo'x, if the rounded corners 83d'erfg age'theupperinner corners of the box (i.e.,those corners'located at the upper'edges" of the faces 73), the rounded corners '83 d willtehd 'to camthe'attachment A sidcvtiayst'o obtain proper alignment of the'pads'SS and thesliouldeis71'.' Sinc'ethe attachine'nfA loosely fits on thefork arms F, particularly'ina lateral direction, lateral shiftingmo'vment of the attachment] relative'to th'ffdrki'ar nis 'is permitted? Therefore, despite an initial misalignment; final proper alignment can be obtained.

Also, it' may be assumed that the'attachment is located slightly askew with relation to the box. Thepads 83 that happen to be in approximately their correct positions will tend to'cam the attachmentinto' alignment with the box thus shifting the attachment into a slightly askew positiodrela'tive to fork arms F. Thefsomewhat'loosc fitof the retainers 61 and cross pieces 47 on the fork arms Fwill permit this.

Still further, itis pointed, out that if the misalignment is' more severe than that above assuntei'ratherthan entirely relocatingthe truck for a'second try at alignment, another procedure may be followed. This comprises lowering the fork'arms F 'an'extentto bring the attachmen]: into'engagement with the top of the box and'continuing lowering the fork arms until they assumeinte'rmediate positions in the guides 37 and 39. The retainers R permit this since the pins 61 and the cross pieces do not prevent downward movement of the fork arms. This operation substantially frees the attachment from the fork arms and leaves the attachment lying relatively loosely on the top of the box. Under these circumstances, most or all of the pads 83 will rest on the top portions of the box B inwardly of the faces 73, if the misalignment is primarily of the askew type, or one pair of the pads will rest on such top portions and the other pair will rest on the associated shoulder or even be located outwardly of such shoulder, if the misalignment is primarily of the laterally offset type.

Since fork lift trucks usually have steerable rear wheels for greater maneuverability of the fork arms, the rear wheel may now be turned in a desired direction and the truck moved slightly to bump the attachment A toward its aligned position. As soon as the misaligned pads come close to their proper positions, they will cam the attachment toward an aligned condition with the top of the box. The relative freeness of the attachment from the fork arms permits such movement. Yet the freeness is not such as to interfere with normal handling operations of a box.

It is further contemplated that the carriage C may be of the side shift type having a rear portion 101 engaging the mast 13, and a front portion 193 mounted for transverse movement relative to the rear portion. A suitable piston and cylinder unit 165 connects the portions 191 and Hi3 to efiect a desired side shifting of the front portion.

Thus, if proper lateral alignment of the pads 83 and the shoulders 71 is not obtained initially, and this misalignment is more substantial than that heretofore described, the fork arms F and the attachment A can be side shifted to obtain the desired alignment. However, it is contemplated that an operator may become sufficiently skilled that he will not require the side shifting carriage.

The operations above described have been concerned with handling so-called 'full size'boxes. Half-width or size b'oxes' frequently have j to'be handled. Referring to FIG 1A, the half-width' box B is shown resting in a gondolacar G; on the far side of the car from'the' truck T. To handle this box, the rear de'vices D 'must be shifted forwardl "and locked in'holes 131 (FIG. 1) formed'in the side members '31. If the box B is loaded normal y, the box may be lifted after the hooks of the attachmenthave been brought into proper engagement with 'the'lifting lugs of thebox B lf the box is loaded fii heavily, so that lifting it at such a di stance forwardly of the mast 13 would tend to tip thetruckT, a lifting force may be exerted on the box and the truckT backed up to dragthe box B1 to the near side of thegondola Gas shown in FIG. 1B. Thereafter, the attachment'can be disengaged'from the boit' Bi, and the devices D and D relocated as shown, in FIG. 13 to enable theheavilylo'aded box to be safelylifted, since it is now much closerto themast 13. Holes 133- (FIG. 1) are provided in the members 31 to enable the front devicesD to be'locked in the intermediate positions (FIG. 1C) 'along'the members 31.

While the unloading operations have been described with referenceto boxes loaded'in a gondola car, this-is, of course, merely illustrative, 'and unloading operations may readilybe carried out with the boxes loaded so that the bottom portions ar e inaccessible, or at any time it is desired to lift the boxes by the tops thereof."

The holes 53 (FIG. 4) enable the attachment to be located farther from'the mast} when reaching a remotely located load is requir'ed,or closer to the mast when the load is heavy 'and close location to themas't is desirable.

Having described, the invention in what'is considered to be the preferred embodiment thereof, it is'desired that it be understoodthat the invention is not to be limited other than by the provisions of the following claims.

I claim:

1. An attachment for a pair of fork arms of a fork lift truck to enable the truck to pick up a rectangular container which is wider than the distance between the forks and which has shoulders and vertical faces defining a pair of grooves along two of the upper opposite corner portions of the container, and wherein the container has a horizontal, laterally projecting top lifting lug at each end of each groove in spaced relation to the associated shoulder,

said attachment comprising a generally rectangular frame including a pair of spaced, parallel side members connected by a pair of cross members,

means providing spaced, parallel slots beneath said cross members for slidably receiving the fork arms,

latch means for releasably retaining said fork arms in said slots and beneath said cross members,

a forward and a rearward load engaging unit for each side member, each unit being mounted for sliding movement lengthwise of its side member,

each unit including a hook opening in a forward direction for engaging a lug,

each unit also including a gauging means,

the spacing between the two forward gauging means being slightly narrower than the spacing between the vertical faces of said grooves so that said forward gauging means will seat in said grooves and locate the associated hooks in positions for engaging the associated lugs,

the rearward gauging means being similarly located in relation to said grooves,

each forward gauging means being disposed rearwardly of its hook,

each rearward gauging means being disposed forwardly of its hook so that such gauging means and book can straddle the associated lug to assist in positioning said attachment on said container,

2. An'attachment'for a pairrof angular fork arms of i a fork lift truck to enable the truck to pick up a rectangular container which is wider than the distance between the forks and which has shoulders and vertical faces defining a pair of grooves along two of the upper opposite corner portions of the container, and wherein the container has a horizontal, laterally projecting top lifting lug at each end of each groove in spaced relation to the associated shoulder, said attachment comprising a generally rectangular frame including a pair of spaced, parallel side members connected by a pair of cross members, means providing spaced, parallel slots beneath said cross members for slidably receiving the horizontal portions of the fork arms, a

latch means for releasably retaining said fork arms in said slots and beneath said cross members, said latch means including abutment means to engage the for- Ward faces of the vertical portions of the fork arms, and latch elements for engaging the rear faces of such vertical portions,

a forward and a rearward load engaging unit for each side member, each unit being'rnounted for sliding movement lengthwise of its side member,

each unit including a hook opening in a forward direction for engaging a lug, v each unit also including a gauging means,

the spacing between the two forward gauging means being slightly narrower than the spacing between the vertical faces of Said grooves so that said forward gauging means will seatin said grooves and locate the associated hooks in positions for engaging the associated lugs, a

the rearward gauging means being similarly located in relation to said'grooves, 7

each forward gauging means being disposed rearwardly of its hook, I i I i 7 each rearward gauging means being disposed forwardly of its hooks so that such gauging means and hook can straddle the associated lug to assist in positioning said attachment on said container,

and means for'detachably holding said units in different positions along said side member for engaging diiferent size containers,

said cross membersbeing located substantially above said hooks and said gauging means so that said fork arms will assume a position above the con- 7 tainer at the time the attachment is applied to the container. 7

References Cited in the file of this patent UNITED STATES PATENTS 1,828,308 Been Oct. 20, 1931 1,838,139 Fitch Dec. 29, 1931 2,547,502 Smith et a1 Apr. 3, 1951 2,558,388 Richardson June 26, 1951 2,696,317 Toifolon Dec. 7, 1954 2,807,493 Ryan et al Sept. 24, 1957 7' FOREIGN PATENTS 7 1,001,473 Germany June 24, 1957 1,047,718 Germany Dec. 24, 1958 

1. AN ATTACHMENT FOR A PAIR OF FORK ARMS OF A FORK LIFT TRUCK TO ENABLE THE TRUCK TO PICK UP A RECTANGULAR CONTAINER WHICH IS WIDER THAN THE DISTANCE BETWEEN THE FORKS AND WHICH HAS SHOULDERS AND VERTICAL FACES DEFINING A PAIR OF GROOVES ALONG TWO OF THE UPPER OPPOSITE CORNER PORTIONS OF THE CONTAINER, AND WHEREIN THE CONTAINER HAS A HORIZONTAL, LATERALLY PROJECTING TOP LIFTING LUG AT EACH END OF EACH GROOVE IN SPACED RELATION TO THE ASSOCIATED SHOULDER, SAID ATTACHMENT COMPRISING A GENERALLY RECTANGULAR FRAME INCLUDING A PAIR OF SPACED, PARALLEL SIDE MEMBERS CONNECTED BY A PAIR OF CROSS MEMBERS, MEANS PROVIDING SPACED, PARALLEL SLOTS BENEATH SAID CROSS MEMBERS FOR SLIDABLY RECEIVING THE FORK ARMS, LATCH MEANS FOR RELEASABLY RETAINING SAID FORM ARMS IN SAID SLOTS AND BENEATH SAID CROSS MEMBERS, A FORWARD AND A REARWARD LOAD ENGAGING UNIT FOR EACH SIDE MEMBER, EACH UNIT BEING MOUNTED FOR SLIDING MOVEMENT LENGTHWISE OF ITS SIDE MEMBER, EACH UNIT INCLUDING A HOOK OPENING IN A FORWARD DIRECTION FOR ENGAGING A LUG, EACH UNIT ALSO INCLUDING A GAUGING MEANS, THE SPACING BETWEEN THE TWO FORWARD GAUGING MEANS BEING SLIGHTLY NARROWER THAN THE SPACING BETWEEN THE VERTICAL FACES OF SAID GROOVES SO THAT SAID FORWARD GAUGING MEANS WILL SEAT IN SAID GROOVES AND LOCATE THE ASSOCIATED HOOKS IN POSITIONS FOR ENGAGING THE ASSOCIATED LUGS, THE REARWARD GAUGING MEANS BEING SIMILARLY LOCATED IN RELATION TO SAID GROOVES, EACH FORWARD GAUGING MEANS BEING DISPOSED REARWARDLY OF ITS HOOK, EACH REARWARD GAUGING MEANS BEING DISPOSED FORWARDLY OF ITS HOOK SO THAT SUCH GAUGING MEANS AND HOOK CAN STRADDLE THE ASSOCIATED LUG TO ASSIST IN POSITIONING SAID ATTACHMENT ON SAID CONTAINER, AND MEANS FOR DETACHABLY HOLDING SAID UNITS IN DIFFERENT POSITIONS ALONG SAID SIDE MEMBER FOR ENGAGING DIFFERENT SIZE CONTAINERS, SAID CROSS MEMBERS BEING LOCATED SUBSTANTIALLY ABOVE SAID HOOKS AND SAID GAUGING MEANS TO THAT SAID FORK ARMS WILL ASSUME A POSITION ABOVE THE CONTAINER AT THE TIME THE ATTACHMENT IS APPLIED TO THE CONTAINER. 